This invention relates generally to communication systems, and, more particularly, to wireless communication systems.
Conventional wireless communication systems use a network of base stations or other access nodes to provide wireless connectivity to a large and often mobile population of access terminals. Each access terminal can be identified to the wireless communication system by an identifier that is permanently assigned or “burned in” to the mobile unit. For example, implementations of WiMAX release 1 that are based on the standards and protocols defined by IEEE 802.16e (2009) use a constant 48-bit mobile station identifier (MS-ID) to identify the access terminals in the network. The MS-ID is typically installed or programmed by the manufacturer of the access terminal in the form of a media access control (MAC) identifier. For another example, wireless communication systems that operate according to the Global System for Mobile communications (GSM) and/or Universal Mobile Telecommunication Services (UMTS) standards and/or protocols may use a 64-bit International Mobile Subscriber Identity (IMSI) to identify each mobile unit or access terminal.
The conventional mobile station identifier is used to identify the access terminal within the network and over the air. For example, access terminals can be paged over the air by transmitting a hashed value derived from the identifier, e.g., a 24-bit hash of a 48-bit identifier can be used to page access terminals. Access terminals can also be associated with different identifiers in different circumstances. For example, WiMAX networks that operate according to IEEE 802.16m standards and/or protocols may identify access terminals using a set of identification numbers that range in length from 10 bits to 72 bits depending on the operational state of the access terminal Consequently, the identifier that is used by the network and over the air varies as the operational mode changes, e.g., as the access terminal shifts between sleeping, dormant, idle, active, or other operational states. For example, idle access terminals that comply with IEEE 802.16m can be identified by an 18-bit de-registration identifier that can be used to page access terminals over the air interface.